Astronomy Picture of the Day -- Seasonal Dark Streaks on Mars

NASA ^ | August 08, 2011 | (see photo credit)

[SunkenCiv]

Explanation: What is causing these dark streaks on Mars? A leading hypothesis is flowing -- but quickly evaporating -- water. The streaks, visible in dark brown near the image center, appear in the Martian spring and summer but fade in the winter months, only to reappear again the next summer. These are not the first markings on Mars that have been interpreted as showing the effects of running water, but they are the first to add the clue of a seasonal dependence. The above picture, taken in May, digitally combines several images from the the HiRISE instrument on the Mars Reconnaissance Orbiter (MRO). The image is color-enhanced and depicts a slope inside Newton crater in a mid-southern region of Mars. The streaks bolster evidence that water exists just below the Martian surface in several locations, and therefore fuels speculation that Mars might harbor some sort of water-dependent life. Future observations with robotic spacecraft orbiting Mars, such as MRO, Mars Express, and Mars Odyssey will continue to monitor the situation and possibly confirm -- or refute -- the exciting flowing water hypothesis.

[SunkenCiv]

[Credit: HiRISE, MRO, LPL (U. Arizona), NASA]

[SunkenCiv]

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[count-your-change]

Martians snowboarding down the slopes.

[mikrofon]

Only his hairdresser knows for sure....

[left that other site]

Very Striking Picture! Thank You!

[TheOldLady]

It would be nice if we could see the true colors. I keep thinking that Mars must have a lot of copper when I see these false-color images, LOL!

[Prospero]

If this is a seasonal water sublimation, one would expect the build up of mineral layers, like stelagtites, at those contacts, and that might be precisely what we are seeing here.

Interesting.

[Logic n' Reason]

Easy!! He did it!

[SunkenCiv]

It'll never take me alive. ;') It's iron oxide.

• Red planet's hue due to meteors, not water -- "There is something of a paradox about Mars," agrees Joshua Bandfield of Arizona State University in Tempe. His team recently showed that the planet has no large deposits of carbonates, which should have formed if giant pools of water had persisted on the surface. Bandfield suggests that liquid water must have occasionally burst out of the ground, carving channels and gullies, but that it quickly froze again in the frigid Martian climate.

[TheOldLady]

Lots of speculation. Needs a manned mission. Sigh... I hate what zer0 has done. [pouts]

Fifty years ago, I thought we’d have all this stuff sorted out by now. But no. [reeeeally pouts]